The dishwasher is one of the most useful appliances in the modern kitchen, saving both time and effort. Yet despite its convenience, not everything should be placed inside it. The combination of high temperatures, powerful detergents and intense water pressure can damage certain materials and shorten the lifespan of many kitchen tools.
Although it may seem that almost everything can safely go into the dishwasher, several items require gentler care and should always be washed by hand.
Cast-iron cookware: Cast-iron pans and pots require special care. Dishwashers can strip away their protective seasoning layer, leaving the metal exposed and prone to rust.
High-quality knives: Good kitchen knives lose their sharpness more quickly in the dishwasher. The blades can dull due to moisture and collisions with other utensils during the wash cycle.
Crystal glassware: Delicate crystal items are extremely sensitive. The heat and vibration inside the dishwasher can cause cracks or even breakage.
Wooden utensils: Wooden spoons, cutting boards and similar items absorb water easily. Exposure to prolonged moisture can cause them to swell, warp or crack. These should always be washed by hand and dried thoroughly.
Non-stick cookware: Frequent dishwasher cleaning can damage the non-stick coating of pans, reducing their performance. It is best to follow the manufacturer’s cleaning instructions.
Copper items: Copper utensils can lose their shine or change colour when exposed to strong dishwasher detergents.
Plastic containers: Not all plastics are dishwasher-safe. Those that are should always be placed on the top rack to avoid warping from high temperatures.
Baking trays and moulds: Over time, dishwasher cleaning can dull their surface and cause discoloration.
Disposable aluminium trays: These can leave dark residue on both the tray itself and other items inside the dishwasher.
Decorative plates: Plates with gold trim or decorative finishes can fade or lose their detailing after repeated dishwasher cycles.
Vacuum flasks and thermoses: The dishwasher can damage their internal structure, allowing water to seep between the insulated layers and reducing their ability to retain heat.
Handmade or clay cookware: The glaze or paint on handmade pottery may deteriorate, and the items themselves may crack over time in the dishwasher.
Enamel-coated cookware: Frequent dishwasher use may dull the enamel surface and make the cookware appear worn.
Graters and sharp tools: Dishwasher washing can dull their edges or even damage the interior components of the appliance.
Items held together with glue: Heat and moisture can weaken adhesive joints and cause parts to loosen.
Cracked ceramics: Water can seep into tiny cracks and worsen the damage, eventually causing the item to break.
Why proper care matters
Taking care of kitchenware is not only about cleanliness but also about preserving quality and durability. Before placing an item in the dishwasher, it is always worth checking whether it is truly dishwasher-safe.
